1. Field of Invention
The present invention relates to the high temperature rechargeable battery system using oxygen ion conducting electrolyte which could be capable of utilizing renewable energy sources such as solar or wind power for energy storage and efficiently converting GHG, into useable syngas, solid carbon and oxygen. The byproducts which have good market values can be used as fuel or for further processing. The usage of cheaper electrode materials (i.e. Ti/TiO2, Mg/MgO) other than Lithium can significantly reduce material cost of the scaled-up battery system and work efficiently at higher temperature without sacrificing safety.
2. State of the Art
As we continue our dependence on fossil fuels, there is an ever increasing need for the control and regulation of the greenhouse gases that are emitted during the burning of coal, oil and natural gas. Coal, oil and natural gas continue to supply close to 90% of the world's current energy needs, however their use comes at a cost, as the greenhouse gases emitted during their use, most notably, CO2, is a significant driver of global climate change. It was reported that arctic CO2 levels on Jun. 1, 2012 has exceeded the symbolic 400 ppm level, a level that scientists agree point to a more rapid increase in the global mean temperature.
Current approaches for the reduction of CO2 emission from large-scale fossil fuel facilities focus on carbon capture and storage (CCS) [Advanced Research Projects Agency—Energy, IMPACCT 2009]. Capture of CO2 for recycling, which is faced with several challenges as it is still in its infancy and very costly, can be achieved by absorption processes employing amines or carbonates as absorbents. The regeneration requires heating of the absorbent. This process consumes a significant portion (˜25%) of the power plant energy output. Thus, energy consumption of the process must be reduced in order to fully realize the utility of CO2 recycling. Moreover, the captured CO2 is to be sequestrated to a permanent place which is another energy-consuming process and eventually, available/suitable sites for CCS sequestration will be limited.
Other preferable technology currently being examined is using captured, anthropogenically produced CO2 for the synthesis of syngas through the use of catalysts or solid oxide electrolyte cells (SOEC) [A. Ambrosini, et al., Advances in CO2 Conversion and Utilization, Chapter 1, 1-13, American Chemical Society 2010; F. Bidrawn, et al., Electrochemical and Solid-State Letters, 11 (9), 2008, p. B167-B170; M. R. Haines, et al., Journal of Power Sources, 106, 2002, p. 377-380; A. Amorelli, et al, Energy, 29, 2004, p. 1279-1284, C. M. soots, 2006 Fuel Cell Seminar, INL/CON-06-11719, Q. Fu, C. Mabilat, et al, Energy & Environmental Science, 3, 2010, p. 1382-1397]. Syngas can be utilized as substitute fuel gas for power plants or existing industrial boilers. Syngas can also be further processed into hydrocarbon and carbonaceous fuels, such as Diesel, Methanol, Ammonia, and so on. These techniques, in order to be successful, would have to be reproducible, high performing and have long-term stability and relatively low energy consumption. Recently, a new CO2-rich gas-utilizing battery has been developed [Kensuke Takechi, et al. (2011), Chem. Commun., 47, 3463-3465]. This Li—O2/CO2 battery utilizes a mixed gas of O2 and CO2, and has nearly three times of discharge capacity than that of a standard Li—O2 battery. The disadvantage of it is that this kind of new battery is non-rechargeable due to the difficulty of electrochemical decomposition of Li2CO3 in the cathode.